Our ancestors began on 24 August, exactly four months before Christmas Eve, with the preparation of Christmas. On this day, the Bartholomew day, the geese have been patterned on the pastures and the carp in the ponds, and it was started with the pole for Christmas. Today the Christmas goose is mostly not longer from the own farm and the carp can be found in most families only at 31 december or at the beginning of next year. In Neinerlaa carp has been substituted by herring.

Not only the Bartholomew day is almost forgotten today, but it was among the first puzzle types (if it was not the first at all) of that I made my first puzzles. They are called Sudoku walls, although it is not a Sudoku variant. Let us use this opportunity to remember not just the Bartholomew day, but also this puzzle type.

Fill the grid with the numbers 1 to 8, so that in each row and each column each number occurs exactly once. On no stone two even or two odd numbers should be.